REMOVE

1. rivers
2. boats
3. hills
4. telephone poles
5. 1936

WHAT

1. Grand Coulee Dam (dam) (1)
2. Visual works (hierarchy n … (1)
3. construction equipment (1)
4. construction sites (1)

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WHERE

1. Nespelem, Washington (1)

WHO

1. Still, Clyfford (1)

WHEN

1. Regionalist (American Sce … (1)